Giraffe

Giraffes (genus Giraffa) are large African hoofed mammals. They are the tallest living terrestrial animals and the largest ruminants on Earth. They are classified under the family Giraffidae, along with their closest extant relative, the okapi. Traditionally, giraffes have been thought of as one species, Giraffa camelopardalis, with nine subspecies. Most recently, researchers proposed dividing them into four extant species, with seven subspecies, which can be distinguished morphologically by their fur coat patterns. Six valid extinct species of Giraffa are known from the fossil record. The distinguishing characteristics of giraffes are their extremely long neck and legs, horn-like ossicones, and spotted coat patterns. Their scattered range extends from Chad in the north to South Africa in the south and from Niger in the west to Somalia in the east. Giraffes usually inhabit savannahs and woodlands. Their food source is leaves, fruits, and flowers of woody plants, primarily acacia species, which they browse at heights most other ground-based herbivores cannot reach. Lions, leopards, spotted hyenas, and African wild dogs may prey upon giraffes. Giraffes live in herds of related females and their offspring or bachelor herds of unrelated adult males but are gregarious and may gather in large groups. Males establish social hierarchies through "necking", combat bouts in which they use the neck as a weapon. Dominant males gain mating access to females, which bear sole responsibility for rearing the young. Giraffes have intrigued various ancient and modern cultures for their peculiar appearance and have often been featured in paintings, books, and cartoons. They have been extirpated from many parts of their former range. Giraffes are still found in many national parks and game reserves, and estimates as of 2016 indicate there are approximately 97,500 members of Giraffa in the wild. More than 1,600 were kept in zoos in 2010.

Etymology The name "giraffe" has its earliest known origins in the Arabic word zirāfah (زِرَافَةْ), of an ultimately unclear Sub-Saharan African language origin. The Middle English and early Modern English spellings, jarraf and ziraph, derive from the Arabic form-based Spanish and Portuguese girafa. The modern English form developed around 1600 from the French girafe. "Camelopard" () is an archaic English name for the giraffe; it derives from the Ancient Greek καμηλοπάρδαλις (kamēlopárdalis), from κάμηλος (kámēlos), "camel", and πάρδαλις (párdalis), "leopard", referring to its camel-like shape and leopard-like colouration.

Taxonomy

Carl Linnaeus originally classified living giraffes as one species in 1758. He gave it the binomial name Cervus camelopardalis. Mathurin Jacques Brisson coined the generic name Giraffa in 1762. During the 1900s, various taxonomies with two or three species were proposed. A 2007 study on the genetics of giraffes using mitochondrial DNA suggested at least six lineages could be recognised as species. A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes. A 2016 study also concluded that living giraffes consist of multiple species. The researchers suggested the existence of four species, which have not exchanged genetic information between each other for one to two million years. A 2020 study showed that, depending on the method chosen, different taxonomic hypotheses recognizing from two to six species can be considered for the genus Giraffa. That study also found that multi-species coalescent methods can lead to taxonomic over-splitting, as those methods delimit geographic structures rather than species. The three-species hypothesis, which recognises G. camelopardalis, G. giraffa, and G. tippelskirchi, is highly supported by phylogenetic analyses and also corroborated by most population genetic and multi-species coalescent analyses. A 2021 whole genome sequencing study suggests the existence of four distinct species and seven subspecies, which was supported by a 2024 study of cranial morphology. A 2024 study found a higher amount of ancient gene flow than expected between populations. The cladogram below shows the phylogenetic relationship between the four species and seven subspecies based on a 2021 genome analysis. The eight lineages correspond to eight traditional subspecies in the one-species hypothesis. The Rothschild giraffe is subsumed into G. camelopardalis camelopardalis.

The following table compares the different hypotheses for giraffe species. The description column shows the traditional nine subspecies in the one-species hypothesis.

The first extinct species to be described was Giraffa sivalensis from India, the holotype of which was reevaluated as a vertebra of separate species within the genus that was initially described as a fossil of the living giraffe. Another extinct species Giraffa punjabiensis is known from Pakistan. Four other valid extinct species of Giraffa in Africa are Giraffa gracilis, Giraffa jumae, Giraffa pygmaea and Giraffa stillei. "G." pomeli from Algeria and Tunisia is not a Giraffinae species, but a Palaeotraginae species related to Mitilanotherium.

Evolution Giraffes, along with the okapi, are the only living members of family Giraffidae in the order Artiodactyla. They are ruminants of the clade Pecora, along with Antilocapridae (pronghorns), Cervidae (deer), Bovidae (cattle, antelope, goats and sheep) and Moschidae (musk deer). A 2019 genome study (cladogram below) finds that Giraffidae are a sister taxon to Antilocapridae, with an estimated split of over 20 million years ago.

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